Synergistic insecticidal compositions

ABSTRACT

Insecticidal compositions are provided which contain mixtures of certain benzoyl ureas and pesticides. The invention also encompasses a method of controlling insects by subjecting them to an effective amount of the synergistic insecticidal compositions.

This application is a continuation of prior U.S. application Ser. No.393,554 June 30, 1982, now abandoned.

FIELD OF THE INVENTION

This invention relates, in general, to synergistic insecticidalcompositions. In one aspect, this invention relates to compositionswhich contain certain benzoyl ureas in admixture with at least onepyrethroid, carbamate, organophosphate, chlorinated hydrocarbon, or a2-aryl-1,3-cyclohexandione. In a further aspect, this invention relatesto a method of controlling insects by the application of insecticidallyeffective amounts of the aforementioned compositions.

BACKGROUND OF THE INVENTION

It is known that combinations of certain pesticides with insect growthregulators provide synergistic kill of arthropods. For example, Plapp F.W. Jr., Journal of Economic Entomology, Volume 69, Number 1, pages91-92, (1976), reported that chlordimeform synergized organophosphates,pyrethroids, a carbamate, a chlorinated hydrocarbon and diflubenzuronagainst larvae of an insecticide resistant population of Heliothisvirescens (F). The prior art also teaches that mixtures of pesticidesprovide synergistic kill of arthropods. For example, U.S. Pat. No.4,144,331 discloses synergistic combinations containing chlorofenvinphosand esters of carboxylic acid for control of diptera and ticks. Europeanpatent 0000962 Al describes synergistic pesticidal compositions whichcomprise a pyrethroid insecticide andN,N-di-(2,4-xylyl-aminomethyl)-methylamine (also known as amitraz). Itis claimed in U.S. Pat. Nos. 4,173,637 and 3,748,356 that mixtures ofcompounds described in these two patents with other insecticides,miticides and plant growth regulators, sometimes produce synergisticeffects.

Although the aforementioned references indicate that a synergisticeffect is obtained when certain compounds are combined with specificknown insecticides, there is no broad teaching that such compounds wouldhave the same effect when mixed with other insecticides.

For example, U.S. Pat. Nos. 4,173,637 and 3,748,356 previouslymentioned, disclose that the mixtures of the compounds described inthose two patents with other insecticides, miticides and plant growthregulators sometimes produce synergistic effects. However it has beenobserved that mixtures containing Dimilin orN-(2-chlorobenzoyl)N'-[4(3,5-dibromopyridyl-2-oxy)phenyl]urea, twocompounds described in U.S. Pat. Nos. 3,748,356 and 4,173,637,respectively, and piperonyl butoxide do not produce synergistic kill ofmany insects, such as the armyworm.

Moreover, to attempt to determine which synergist would be effectivewith which insecticide by a trial and error technique is beyond theeconomic capability of most research laboratories. Hence, it was indeedunexpected and surprising to find that certain pesticides were effectivewhen employed in admixture with certain benzoyl urea insecticides. Thus,according to the present invention it was found that the amount ofbenzoyl urea insecticide can be greatly reduced resulting not only ineconomic savings but more importantly protecting the natural environmentas well.

Accordingly, one or more of the following objects can be achieved by thepractice of this invention. It is an object of this invention to providenovel insecticidal compositions which contain mixtures of a pesticideand certain benzoyl ureas. Another object of this invention is toprovide insecticidal compositions containing mixtures of pyrethroids andcerain benzoyl ureas. A further object of this invention is to providecompositions containing mixtures of carbamates and certain benzoylureas. Another object is to provide insecticidal compositions containingmixtures of organophosphates and certain benzoyl ureas. A further objectis to provide mixtures of chlorinated hydrocarbons and benzoyl ureas.Another object of this invention is to provide synergistic insecticidalcompositions of 2-aryl-1,3-cyclohexandiones and benzoyl ureas. A stillfurther object of the invention is to provide insecticidal compositionswherein the active toxicant can be employed in a reduced amount andstill achieve the desired insect control. A still further object of theinvention is to provide a method for controlling insect growth by theapplication of the compositions of this invention. Those and otherobjects will readily become apparent to those skilled in the art in thelight of the teachings herein set forth.

SUMMARY OF THE INVENTION

In its broad aspect, the invention is directed to synergisticinsecticidal compositions and to a method for their use. As indicatedabove, the synergistic insecticidal compositions of this invention arecomprised of a mixture of a benzoyl urea and at least one pyrethroid,carbamate, organophosphate, chlorinated hydrocarbon, or a2-aryl-1,3-cyclohexandione.

DETAILED DESCRIPTION OF THE INVENTION

As indicated above, the synergistic insecticidal composition of thisinvention are comprised of (a) a benzoyl urea component and (b) at leastone other component which is a known pesticide.

The benzoyl urea component of the compositions of this inventionencompasses compounds of the general structure: ##STR1## Wherein R₁ andR₂ are independently H, Cl, F, OCH₃ or CH₃ ; R₃ and R₄ are H, Cl or CF₃; R and R₆ are independently H, halogen, CN, NO₂ or CF₃, and X is CH orN.

Particularly useful composition of the general structure I are thosewherein R₁ is chloro or fluoro, R₂ is hydrogen or fluoro, R₃ and R₄ arechloro and X is nitrogen. R₅ may be 3-chloro, and R₆ is5-trifluoromethyl. When X is CH, R₆ may be 4-nitro.

Illustrative benzoyl ureas are compounds such as,

4-nitro-4'-[N-(N'-2-chlorobenzoyl)-ureido]-diphenyl ether,

4-nitro-2', 6'-dichloro-4'-[N(N'-2,6-difluorobenzoyl)ureido]-diphenylether,

4-nitro-4'-[N-(N'-2,6-difluorobenzoyl)-ureido]-diphenyl ether,

4-nitro-2,',6'-dichloro-4'-[N-(N'-2-fluorobenzoylureido]-diphenyl ether,

4-nitro-2',6'-dichloro-4'-[N-(N'-2-methylbenzoyl)ureido]-diphenyl ether,

4-nitro-2',6'-dichloro-4'-[N'-2,6-dichlorobenzoyl)ureido]-diphenylether,

N-(2,6-difluorobenzoyl)N'-4-(3-chloro-5-trifluoromethyl-pyridyl-2-oxy)phenyl]urea,

N-(2,6-difluorobenzoyl)N'-[3,5-dichloro-4-(5-trifluoromethylpyridyl-2-oxy)phenyl]urea,

N-(2,6-difluorobenzoyl)N'-[3,5-dichloro-4(3-chloro-5trifluoromethylpyridyl]-2-oxy)phenyl]urea,

N-(2,6-difluorobenzoyl)N'-[3-chloro-4-(3-chloro-5-trifluoromethylpyridyl-2-oxy)phenyl]urea,

N-(2-chlorobenzoyl)N'-4[3,5-dibromopyridyl-2-oxy)phenyl]urea, and thelike.

The benzoyl ureas employed in this invention are prepared by one or moreprocedures disclosed in the literature. For example, the4-nitro-4'-[N-(N'benzoyl)-ureido]diphenyl ethers are prepared either byreacting a nitro-phenoxyaniline with a benzoyl isocyanate or by reactinga 4-isocyanato-diphenyl ether with a benzamide. Further details for thepreparation of the nitro diphenyl ether derivatives are set forth inU.S. Pat. No. 4,041,177.

Benzoyl ureas wherein X in the above formulas is nitrogen can beprepared by the methods disclosed in U.S. Pat. No. 4,173,637. Forexample, a benzoyl isocyanate can be reacted with pyridyloxy aniline ora benzamide can be reacted with a pyridyloxy phenyl isocyanate.

The second component of the synergistic insecticidal compositions ofthis invention is a pesticide of the group of pyrethroids, carbamates,organophosphates, chlorinated hydrocarbons, and2-aryl-1,3-cyclohexadiones These pesticides are of the following groups:##STR2## wherein R₇ is: ##STR3## wherein R₈ is: ##STR4## and M is Cl,OCHF₂ or OCF₃ ; n is zero or 1; and Z is H, CH₃, C.tbd.CH or C.tbd.N;##STR5## wherein R₉ is alkylphenoxy, 1-naphthyl, 2,3-dihydro-2,2-dimethylbenzofuran-7-yl-oxy, 3,4,5-trimethylphenyl,4-(methylthio)3,5-xylyl or 2,2-dimethyl-1,3-benzodioxol-4-yl. Thecarbonates, thiodicarb and methomyl can also be employed. ##STR6##wherein B is O or S; R₁₀ is aryl or substituted aryl where thesubstituents may be one or more groups selected from nitro, chloro,bromo, alkylthio, alkylsulfinyl, alkyl or alkylsulfonyl; R₁₁ is loweralkyl, R₁₂ is alkyl, aryl or alkylthio, with the proviso that R₁₀, R₁₁,or R₁₂ individually may not contain more than 18 carbon atoms; ##STR7##wherein R₁₃ is lower alkyl, R₁₄, R₁₅ or R₁₆ are independently hydrogenor lower alkyl, and Y is an alkanoyl ester of 2 to 12 carbons; and

Chlorinated aliphatic cycloaliphatic and aromatic hydrocarbons VIcontaining up to 8 chlorine atoms and up to 24 carbon atoms and whichmay optionally be substituted with up to 2 lower alkoxy groups or ishydropyl group.

Illustrative compounds encompassed by the above formulae include, butare not limited to, (permethrin)3-(phenoxy-phenyl)methyl-3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropane carbonxylate; (fenvalerate) cyano(3-phenoxyphenyl)methyl-4-chloro-alpha-(1-methylethyl)benzene acetate; (BPMC) 2-(1-methylpropyl)phenyl methylcarbamate;(carbofuran)2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate;(carbaryl)1-naphthyl methyl carbamate; (thiodicarb)dimethyl-N,N'-[thiobis (methyliminocarbonyloxy)] bis[ethanimidiothioate]; (methomyl)methyl (methyliminocarbonyloxy)ethanimidothioate;(malathion) 0,0-dimethylphosphorodithioate of diethylmercapto-succinate; (methyl-parathion)0,0-dimethyl-0-p-nitrophenylphosphorothioate; (acephate) O,S-dimethylacetylphosphoramidothioate; (azinophos-methyl) O,O-dimethylS-[4-oxo-1,2,3-benzotriazin-3(4H)-yl) methyl] phosphorodithioate;(profenofos)0-(4-bromo-2-chlorophenyl)-0-ethyl-S-propyl-phosphorothioate;3-(2-ethylhexanoyloxy)-5,5-dimethyl-2-(2'methylphenyl)-1-cyclohexanone;3-(2-ethylhexanoyloxy)5,5-dimethyl-2-(2',4'-dimethylphenyl)-2-cyclohexane; (DDT)1,1,1-trichloro-2,2-bis-(p-chlorophenyl)ethane; (dicofol)4-chloro-alpha-(4-chlorophenyl)-alpha-(trichloromethyl)benzenemethanol;(methoxychlor) 2,2-bis(p-methoxyphenyl)-1,1,1-trichloroethane;(chlordome)1,2,4,5,6,7,8-octachloro-2,5,3a,4,7,7a-hexahydro-4,7-methano-(H-indene);and (Lindane) hexachlorocyclohexane and the like.

The proportion of the benzoylureas to the pesticide can vary over a widerange depending on such factors as the particular locus to be treated,the particular pest to be combatted and the particular effect desired.The weight proportion of the benzoylurea to the pesticide may be, forexample, from 1:0.5 to 1:1000, respectively. Usually there is a greaterproportion of pesticide than the benzoylurea. Preferably, the proportionof pesticide to the benzoylurea are 5:1 to 500:1, respectively.

In the practice of the novel compositions of the present invention, thepesticide is mixed with the benzoylurea and a suitable inert carrierwhich may be a solid or a liquid. One suitable method of preparing thecompositions of the present invention is to mix the pesticide with orwithout solvent or diluent, with a suitable carrier and then mix theresulting composition with the benzoylurea with or without solvent.

The novel pesticidal compositions of the present invention willtypically include conventional pest control adjuvants, diluents,modifiers or conditioning agents, herein included in the term "suitablecarrier substance", to provide compositions in the form of solutions,emulsions, dispersions, powders, dusts, granules pellet and the like.Thus, the pesticidal compositions can be either liquids or solids. Theliquid compositions can contain one or more surface active agents as aconditioning agent to render the composition readily dispersable inwater. The term surface active agents includes wetting agents,dispersing agents, emulsifying agents and the like. The solidformulations of the present invention in the form of powder, dust,pellets or granules can be prepared using such substances as talc,natural clay, pyrophyllite, diatomaceous earth, walnut shells, corncobs, sugar, sand and the like.

Suitable liquid diluents or carriers include water, petroleumdistillates, or other liquid carriers with or without surface activeagents. Liquid concentrates may be prepared by dissolving one of thesecompositions with a non-phytoxic solvent such as acetone, xylene, ornitro-benzene and dispersing the toxicants in water with the aid ofsuitable surface active emulsifying and dispersing agents.

The choice of dispersing and emulsifying agents and the amount employedis dictated by the nature of the composition and the ability of theagent to facilitate the dispersion of the toxicant. Generally, it isdesirable to use as little of the agent as is possible, consistent withthe desired dispersion of the toxicant in the spray so that rain doesnot re-emulsify the toxicant after it is applied to the plant and washit off the plant. Nonionic, anionic, or cationic dispersing andemulsifying agents, for example, the condensation products of alkyleneoxides with phenol and organic acids, alkyl aryl sulfonates, complexether alcohols, quaternary ammonium compounds, and the like may beemployed for this purpose.

In the preparation of wettable powder or dust or granulatedcompositions, the active ingredient is dispersed in and on anappropriately divided solid carrier such as natural clay, talc,pyrophyllite, bentonite, diatomaceous earth, fullers earth, corn cobs,and the like. In the formulation of the wettable powders theaforementioned dispersing agents as well as lignosulfonates can beincluded.

The required amount of the toxicants contemplated herein may be appliedper acre treated in from 1 to 200 gallons or more of liquid carrierand/or diluent or in from about 5 to 500 pounds of inert solid carrierand/or diluent. The concentration in the liquid concentrate will usuallyvary from about 10 to 95 percent by weight and in the solid formulationsfrom about 10 to 95 percent by weight. Satisfactory sprays, dust, orgranules for general use contain from about 1/4 to 15 pounds of activetoxicant per acre.

The insecticides contemplated herein prevent attachment by insects uponplants or other material to which the insecticides are applied. Withrespect to plants, they have a high margin of safety in that when usedin sufficient amount to kill or repel the insects, they do not burn orinjure the plant, and they resist weathering which includes wash-offcaused by rain, decomposition by ultra-violet light, oxidation, orhydrolysis in the presence of moisture or, at least, such decomposition,oxidation, and hydrolysis as would materially decrease the desirableinsecticidal characteristics of the toxicants or impart undesirablecharacteristics, for instance, phototoxicity, to the toxicants. Thetoxicants are compatible with other constituents of the spray schedule,and they may be used in the soil, upon the seeds, or the roots ofplants. Mixtures of the synergistic insecticidal compositions of thisinvention may be employed if desired as well as combinations of thesynergistic insecticidal compositions with one or more fungicides,bactericides, acaricides, nematicides, insecticides or otherbiologically active compounds.

The synergistic insecticidal compositions of this invention areeffective against a wide variety of insects. It is understood that theSouthern armyworm evaluated in the working Examples herein isrepresentative of a wider variety of insect which can be controlled bythe synergistic insecticidal compositions of this invention. Thesecompositions are particularly useful in controlling insects ofagricultural crops, e.g., potatoes, maize, sugar beets, cotton, rice,wheat, tobacco, soybeans, deciduous and citrus fruits.

The joint action of the two pesticides employed in the insecticidalcomposition of this invention was analyzed according to the method ofYun-Pei Sun and E. R. Johnson, Journal of Economic Entomology, 1960,Volume 52, No. 5, pages 887-892.

Thus, the join action of two pesticides was analyzed by determining theactual toxicity indices of the components and of mixtures of thecompounds by reference to dosage-mortality curves. The theoreticaltoxicity of the mixture is equal to the sum of toxicity indicescalculated from the percentage of each component multiplied by itsrespective toxicity index. Therefore, the joint toxicity: ##EQU1##

A coefficient of a mixture near 100 indicates probability of similaraction by the two pesticides; independent action usually, should give acoefficient less than 100, while coefficient significantly above 100strongly indicates synergism.

The following examples illustrate the best mode presently contemplatedfor the practice of this invention:

EXAMPLE 1 Use of a mixture of N-(2,6 difluorobenzoyl)-N'-[3,5-dichloro-4-(3-chloro-5-trifluoromethyl pyridyl-2-oxy)phenyl]ureaand other pesticides for control of Southern armyworm larvae (Spodopteraeridania

Aqueous suspension of benzoylurea and pesticides listed in Table 1 wereprepared by dissolving 1 gram of each compound in 50 milliliters ofacetone in which had been dissolved 0.1 gram (10 percent by weight ofeach compound to be tested) of an alkylphenoxy polyethyoxyethanolsurfactant as an emulsifying or dispersing agent. The resultingsolutions were mixed with 150 milliliters of water to give 200milliliters of a suspension containing each test compound in finelydivided form. The thus-prepared stock suspension contained 0.5 percentby weight of each compound. The concentration employed in the testresults presented below were obtained by diluting the stock suspensionswith water. Potted tendergreen bean plants of standard height and agewere placed on a revolving turntable and sprayed with 100-110milliliters of test compound formulation by use of a De Vilbiss spraygun set at 40 psig air pressure. This application, which lasted 25seconds, was sufficient to wet plants to run-off. As a control, 100-110milliliters of a water-acetone-emulsifier solution containing no testcompound were also sprayed on infested plants. When dry, the pairedleaves were separated and each one was placed in a 9 centimeter Petridish lined with moistened filter paper. Five randomly selected larvaewere introduced into each dish and the dishes were closed. The closeddishes were labeled and held at 80°-85° F. for three days. Although thelarvae could easily consume the whole leaf within twenty-four hours, nomore food was added. Larvae which were unable to move the length of thebody, even upon stimulation by prodding, were considered dead. Per centmortality was recorded for the various concentration levels. LD₅₀(concentration required to kill 50 per cent of the armyworm larvae)volume were determined from the mortality figures.

The results of these tests are set forth in Table 1 below:

                  TABLE I                                                         ______________________________________                                        TOXICITY TO ARMYWORM LARVAE                                                               Weight  LD.sub.50 (ppm)                                                                         Coefficient                                                                           Syner-.sup.(1)                          Compound or ratio of                                                                               Spodoptera                                                                             of      gistic                                  Compound mixture                                                                          mixture eridania  co-toxicity                                                                           ratio                                   ______________________________________                                        A.sup.(2)   1:67    0.7       8794                                            malathion           140                                                       A + malathion       0.4                                                       methyl-parathion    22                                                        A + methyl- 1:6     0.1       4184                                            parathion                                                                     profenofos          9                                                         A + profenofos                                                                            1:16    0.4       1326                                            acephate            11                                                        A + acephate                                                                              1:40    0.5       1628                                            azinophosmethyl     30                                                        A + azinophos-                                                                            1:30    0.16      8102                                            methyl                                                                        chlorpyriphos       11                                                        A + chlorpyriphos                                                                         1:16    0.19      3096                                            carbofuran          34                                                        A + Carbofuran                                                                            1:100   0.25      9091                                            carbaryl            96                                                        A + Carbaryl                                                                              1:50    0.7       3676                                            thiodicarb          4.3                                                       A + Thiodicarb                                                                            1.5:5   0.7        241                                            methomyl            7                                                         A + methomyl                                                                              1:5     1.0        250                                            BPMC                500                                                       A + BPMC    1:500   0.2       --      3.5                                     fenvalerate         5.0                                                       A + fenvalerate                                                                           1.5:5   0.8        220                                            permethrin          5.0                                                       A + permethrin                                                                            1.5:5   1.2        147                                            DDT                 31                                                        A + DDT     1:25    0.04       28363                                          dicofol             200                                                       A + dicofol 1:25    0.28      5760                                            methoxychlor        140                                                       A + methoxychlor                                                                          1:25    0.37      4223                                            3-(2-ethylhexano-   500       --                                              yloxy)-5,5-dimethyl-                                                          2-(2'-methylphenyl)-                                                          1-cyclohexanone                                                               A + 500 ppm of      0.28      --      2.3                                     preceding compound                                                            3-(2-ethylhexanoyloxy)-                                                                           500                                                       5,5-dimethyl-2-(2'-4'-                                                        dimethylphenyl)-2-cyclo-                                                      hexanone                                                                      A + 500 ppm of same 0.23      --      3.0                                     preceding compound                                                            ______________________________________                                         ##STR8##                                                                      .sup.(2) A = N(2,6                                                            difluorobenzoyl)N'[3,5dichloro-4-(3-chloro-5-trifluoromethyl--                pyridyl-2-oxy)phenyl]urea.                                               

Although the invention has been illustrated by the foregoing examples,it is not to be construed as being limited to the materials employedtherein; but rather, the invention encompasses the generic area ashereinafter disclosed. Various modifications and embodiments can be madewithout departing from the spirit and scope thereof.

What is claimed is:
 1. A synergistic insecticidal composition comprisingN-(2,6-difluorobenzoyl)-N-[3,5-dichloro-4-(3-chloro-5-trifluoromethylpyridyl-2-oxy)phenyl]ureaand 2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate wherein theweight proportion ratio ofN-(2,6-difluorobenzoyl)-N-[3,5-dichloro-4-(3-chloro-5-trifluoromethylpyridyl-2-oxy)phenyl]ureato 2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate is from 1:0.5to 1:1000.
 2. A method of controlling insects which comprises subjectingsaid insects to an insecticidally effective amount of the synergisticinsecticidal composition of claim 1.